Razor Handle and Shaver Including Such a Handle

ABSTRACT

A razor handle having a handle body and a lock/release mechanism that includes two arms, each having a bearing for pivotally connecting a shaving head, the arms extending substantially symmetrically on both sides of a medial axis, the arms being elastically biased opposite to one another toward a head locking position wherein the bearings are adapted to pivotally bear the shaving head, and the arms being movable toward one another into a head release position wherein the bearings are adapted to release the shaving head. The razor handle also includes a plunger which is movable between the two arms, substantially parallel to the medial axis, and a spring biasing the plunger away from the handle body, such that the plunger is adapted to cooperate with a cam surface belonging to the shaving head for biasing the shaving head toward a rest position.

FIELD OF THE INVENTION

The invention relates to razor handles and to shavers including such handles.

BACKGROUND OF THE INVENTION

More precisely, the invention relates to a razor handle having a handle body and a lock/release mechanism including:

-   -   two arms, each having a bearing for pivotally connecting a         shaving head, said arms extending substantially symmetrically on         both sides of a medial axis, said arms being elastically biased         opposite to one another toward a head locking position wherein         said bearings are adapted to pivotally bear said shaving head,         and said arms being movable toward one another into a head         release position wherein said bearings are adapted to release         said shaving head,     -   a plunger which is movable between said two arms, substantially         parallel to said medial axis,     -   and a spring biasing said plunger away from the handle, such         that said plunger is adapted to cooperate with a cam surface         belonging to the shaving head for biasing said shaving head         toward a rest position.

U.S. Pat. No. 4,888,357 discloses an example of such a known shaver, in which the arms are connected together by a resilient bridge portion which biases the arms in opposite directions. The biasing force transmitted to the arms by the bridge portion may, however, vary in time due to the creeping or wear of the plastic material forming the bridge portion.

OBJECTS AND SUMMARY OF THE INVENTION

One objective of the present invention is to avoid this drawback.

To this end, according to the invention, in a vibrating shaver of the type in question, said lock/release mechanism further includes an arm pusher which is movable substantially parallel to the medial axis and which is biased toward the handle body by said spring, said arm pusher cooperating with the two arms by camming action for biasing the arms toward the head locking position.

Thanks to these dispositions, it is possible to obtain a reliable biasing effort on the arms, without having multiple springs.

In various embodiments of the invention, one may possibly have recourse in addition to one and/or other of the following arrangements:

-   -   the two arms are connected to one another by a hinge;     -   said arms are molded as a single piece, said hinge comprising a         thin bridge of material connecting the two arms to each other;     -   each arm extends between a first end connected to said hinge and         a second end including one of the bearings;     -   said bearings are shell bearings;     -   the arms are partially contained inside said handle body and the         bearings are exposed toward the outside;     -   each arm includes a pushbutton which is adapted to protrude         outside said body when said arms are in the locking position;     -   the two arms diverge from the medial axis in a direction away         from the handle body;     -   the spring is a compression spring interposed between the         plunger and the arm pusher in the medial direction;     -   the spring extends between two spring ends, penetrating         respectively in a recess belonging to the plunger and in a         recess belonging to the arm pusher;     -   the plunger has a central body and two lateral wings, the         central body being adapted to cooperate with the cam surface of         the shaving head to bias said shaving head toward the rest         position, and said central body including said recess of the         plunger which opens toward the arm pusher;     -   the plunger has a central body and two lateral wings, the two         lateral wings of the plunger being adapted to cooperate by         hooking action respectively with the two arms to maintain said         arms in the head release position when the plunger is in an         outwardly protruding position;     -   said lateral wings of the plunger are adapted to release the         arms when the plunger is moved toward the handle body relative         to the outwardly protruding position;     -   the lateral wings of the plunger include detents which protrude         away from the handle body, substantially parallel to the medial         axis, and the arms include two openings adapted to receive said         detents to maintain said arms in the head release position when         the plunger is in an outwardly protruding position;     -   the arm pusher has a central body and two lateral extensions         cooperating by camming action respectively with the two arms for         elastically biasing the arms toward the head locking position;     -   said two lateral extensions penetrate in two slots formed         respectively in the two arms;     -   each slot has a bottom and each lateral extension cooperate by         camming action with the bottom of the corresponding slot;     -   the two extensions of the arm pusher have lateral edges which         diverge from the medial axis in a direction away from the handle         body, said lateral edges bearing respectively on the bottoms of         the slots, and said bottoms also diverging from the medial axis         in a direction away from the handle body.

Besides, another object of the present invention is a shaver including a razor handle as defined above and a shaving head pivotally attached to handle by said bearings, said shaving head including a cam surface and the plunger being elastically biased against said cam surface for biasing said shaving head toward a rest position. The bearings may be shell bearings and the shaving head may further include two inwardly facing arcuate slots receiving respectively the two bearings of the arms.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the invention appear from the following detailed description of one of its embodiments, given by way of non-limiting example, and with reference to the accompanying drawings.

In the drawings:

FIGS. 1 a and 1 b are respectively perspective views of a shaver according to one embodiment of the invention, seen from above and from below,

FIG. 2 is an exploded perspective of the shaver of FIGS. 1 a and 1 b, seen from above,

FIG. 3 is an exploded perspective view of the shaver of FIGS. 1 a and 1 b, seen from below,

FIG. 4 is a longitudinal cross section of the shaver of FIG. 1,

FIGS. 5-7 are respectively transverse cross sections along lines V-V, VI-VI and VII-VII of FIG. 4,

FIGS. 8 a and 8 b are two perspective views, seen in two different directions, of the lock/release mechanism connecting the razor handle to the shaving head in the shaver of FIGS. 1 a and 1 b,

FIG. 9 is a rear view of the shaving head in the shaver of FIGS. 1 a and 1 b,

and FIGS. 10 and 11 are cross sections of the lock/release mechanism of FIGS. 8 a and 8 b, respectively in the head locking position and in the head release position.

In the figures, the same references denote identical or similar elements.

FIGS. 1 a and 1 b show a wet shaver 1, i.e. a shaver the blades of which are not driven by a motor relative to the shaving head.

The shaver 1 includes a hollow handle 2 extending in a longitudinal direction L between a proximal portion 3 and a distal portion 4 bearing a shaving head 5. The shaving head 5 includes a front face 5 a equipped with one or several blades 5 b and a rear face 5 c which is connected to the handle 2.

The longitudinal direction L may be curved or include one or several straight portions. In the present case, the longitudinal direction L is curved, with a concavity which is constantly directed toward the underside 6 of the handle (i.e. the side of the handle which faces substantially the same direction as the front face 5 a of the shaving head).

The shaver may further include, for instance on the top side 7 of the handle (i.e. the side of the handle which faces opposite the front face 5 a of the shaving head), a flexible wall 8 which enables to actuate a switch 9 (see FIGS. 2 and 3) mounted inside the hollow handle 2, for instance by pressing on a pusher 10 of said switch when depressing said flexible wall 8.

The switch 9 controls an electric vibrator 11 (see FIGS. 2-4) which is able to generate vibrations and transmits them to the handle 2. The electric vibrator may include for instance:

-   -   an electric motor 12 having a rigid outer casing 13,     -   an output shaft 14 rotated by the electric motor 12,     -   and an eccentric mass 15 which is mounted on the output shaft         14.

As it will be explained in further details hereafter, the rigid outer casing 13 of the electric motor 12 is tightly fitted in the handle 2, in the vicinity of the distal portion 4, with interposition of an elastomeric layer 16 between the casing and the handle.

The casing 13 may be circular in cross section, and may in particular have substantially the shape of a circular cylinder and the elastomeric layer 16 may surround the casing 13 of the vibrator. The elastomeric layer may be in the form of an elastomeric sleeve surrounding the casing of the vibrator or more generally may include such elastomeric sleeve.

As shown in FIGS. 5-7, the thickness e of the elastomeric layer may be comprised for instance between 0.2 and 1 mm. More particularly, where said elastomeric layer 16 is compressed between the casing 13 and the handle 2, the thickness e may be comprised between 0.2 and 0.6 mm, and for instance be around 0.4 mm, whereas in the portions where said elastomeric layer is not compressed between the casing and the vibrator, the thickness e of such layer may be comprised for instance between 0.4 and 1 mm.

The elastomeric layer 16 may for instance be a silicone layer or more generally may comprise such silicone layer, and said elastomeric layer may have a Shore hardness comprised for instance between 70 Shore A and 90 Shore A. Said Shore hardness may be for instance around 75 Shore A.

In the example considered here, as shown for instance in FIGS. 2 and 3, the handle may include a substantially rigid hollow body 17 (as opposed to softer elastomeric parts of the handle), made out for instance of plastic material, e.g. of molded thermoplastic.

The body 17 may form the distal portion 4 of the handle and the medial portion 18 of said handle, and said body 17 may comprise:

-   -   a first body portion 19 forming for instance part of the top         side 7 of the handle,     -   and a second body portion 20 which may form for instance part of         the underside 6 of the handle.

The first body portion 19 may include a recessed portion 21 on which is fixed an elastomeric trim 22 which includes said flexible wall 8 in correspondence with a hollow portion 23 which is hollowed out in said recessed portion 21 in correspondence with the pusher 10 of the switch 9.

The first body portion 19 may also include a flexible tongue 24 protruding substantially parallel to the longitudinal direction L in the hollow portion 23 and interposed between the flexible wall 8 and the pusher 10. The flexible tongue 24 is elastically flexed and presses on the pusher 10 when a user depresses the flexible wall 8, and said flexible tongue 24 thereafter elastically returns the flexible wall 8 toward its normal position. In this normal position, the flexible wall 8 may for instance slightly protrude upwardly from the elastomeric trim 22.

Besides, the first body portion 19 may also include, in the example shown in the drawings, an index pad 25 on which the index finger of the user of the shaver may rest (see FIG. 2). This index pad 25 may for instance extend with an increasing width, between a rear tip 25 a and a front end which is wider than said rear tip and which is closer to the shaving head 5 (see FIG. 1 a). The index pad 25 may be made for instance out of elastomer.

Besides, as shown for instance on FIGS. 2 and 3, the second body portion 20 may also include an outer recess portion 26 in which is fixed a further elastomeric trim 27. the trim 27 may include for instance transverse ribs 27 a at the end of said trim which is opposite the distal portion 4 of the handle.

The elastomeric trims 22, 27 may be fixed to the corresponding body portions 19, 20 by any suitable means, for instance by co-injection.

The first and second body portions 19, 20 are facing each other in a first transverse direction T1 (FIG. 4) which is substantially perpendicular to the longitudinal direction L at the level of the motor 12 and which is comprised in a medial plane of symmetry of the shaver 1. More precisely, the first transverse direction, as shown in FIG. 4, is perpendicular to the output shaft 14 of the motor.

The first and second body portions 19, 20 may be fixed together by fitting and by ultrasonic welding. However, the first and second body portions could be fixed together by any other means, such as snap fitting, gluing, etc.

The casing 13 of the motor may be for instance tightly fitted between:

-   -   at least one, for instance two concave bearing surfaces 28         belonging to the first body portion 19 and facing toward the         second body portion 20 parallel to the first transverse         direction T1 (see FIGS. 3 and 6),     -   and at least one, for instance two second concave bearing         surfaces 29 belonging to the second body portion 20 and facing         toward the first body portion 19 in the first transverse         direction T1 (FIGS. 2 and 7).

These first and second bearing surfaces, which may be either in mutual correspondence on both sides of the motor 12 or axially offset along the longitudinal direction L of the motor 12, are more clearly visible on FIGS. 6 and 7.

As shown on FIG. 6, the or each first bearing surface 28 may have a substantially U shape, with a base surface 28 a and two substantially parallel side surfaces 28 b facing each other in a second transverse direction T2 substantially perpendicular to the first transverse direction and to the longitudinal direction. These side surfaces 28 b may be disposed to be clamped onto substantially diametrically opposed portions of the casing 13, with interposition of the elastomeric layer 16. This feature enables an easier manufacturing process, since the motor 12 may thus be retained in the first bearing surface 28 after being mounted therein, before mounting of the second body portion 20 onto the first body portion 19.

Besides, in the embodiment shown in the drawings, the elastomeric layer 16 may be more compressed in the second transverse direction T2 between the two side surfaces 28 b of the first bearing surface 28 (FIG. 6), than in the first transverse direction T1 between the second bearing surface 29 and the base surface 28 a of the first bearing surface.

This feature may also facilitate the manufacturing process, particularly since the tolerances of mutual positioning between the second bearing surface 29 and the base surface 28 a parallel to the first transverse direction T1 may be larger than the tolerances between the side surfaces 28 b parallel to the second transverse direction T2. As shown in FIGS. 3 and 4, the casing 13 of the motor is also axially fitted between two abutments, parallel to the longitudinal direction L, to wit a rear abutment 30 belonging for instance to the first body portion and a front abutment 31 which may also belong to the first body portion.

The front abutment 31 which may include a cut out 31 a for the output shaft 14 of the motor, said front abutment being axially interposed between the casing 13 and the eccentric mass 15, preferably without contact between front abutment 31 and said eccentric mass 15.

As shown in FIG. 3, the switch 9 is mounted between the vibrator 11 and the proximal portion 3 of the handle, close to said vibrator 3, and is connected to the motor 12 by electric wires 32. The switch 9 may be fixed to a base plate 33 such as an electronic circuit board, which is itself fitted in support members 34 belonging for instance to the first body portion 19.

Besides, the handle further includes a battery housing 35 (see FIGS. 3 and 4) which is situated between the switch 9 and the proximal portion 3. This battery housing is adapted to receive a battery 36 extending longitudinally substantially parallel to the longitudinal direction L of the handle. This battery may be inserted in and removed from the battery housing 35 parallel to the longitudinal direction L, after removing an end cap 37 which forms the proximal portion 3 of the handle and which is axially fitted at the rear open end 38 of the body 17, said rear end being formed for instance by a portion of circular cross section of the first body portion 19, opposite to the shaving head 5.

As shown in FIGS. 2 and 4, the battery housing may further include two electrical contacts 39, 40 for connecting the battery to the switch. The electrical contact 39 may be in the form of a metallic strip which is fitted inside the end cap 37.

Besides, the end cap 37 may include for instance an upper finger rest portion 37 a with protruding dots on the top surface of the handle, and a lower flattened portion 41 also with protruding dots. Both upper finger rest portion 37 a and lower flattened portion 41 may be formed for instance out of elastomer or include an elastomeric trim.

As discussed previously, the distal portion 4 of the razor handle bears the shaving head 5. As shown in FIGS. 1 a and 1 b, the shaving head 5 includes a front face 5 a having one or several blades 5 b exposed thereon, and a rear face 5 c which is connected to the handle 2.

In the example shown in the drawings, the rear face 5 c of the shaving head is connected to the handle 2 by a lock/release mechanism 41 which is shown in greater details in FIGS. 8 a, 8 b and 10 and which enables to selectively:

-   -   either connect the shaving head 5 to the handle,     -   or release said shaving head in order to exchange shaving heads.

It should be noted that:

-   -   the vibrating mechanism described previously could be used with         another type of connection between the shaving head and the         handle,     -   and that the lock/release mechanism 41, which will now be         described in greater details, could be used without any         vibrating mechanism, or with a different vibrating mechanism.

As shown in greater details in FIGS. 2, 8 a, 8 b and 10, the lock/release mechanism 41 includes two arms 42 which can be made for instance out of molded plastic material. The two arms 42 may each extend from a first end 42 a situated inside the handle body 17 toward a second end 42 b which may protrude toward the outside at the distal portion 4 of the handle 2. The two arms may be disposed in a V shape, diverging from a medial axis X from their first end 42 a toward their second end 42 b. The medial axis X is substantially parallel to the curved longitudinal axis L of the handle.

The first ends 42 a of the two arms 42 may be connected together by a hinge 43, formed for instance as a thin bridge of plastic material connecting the two arms 42 to each other when said arms are molded as a single piece. The hinge 43 may have a negligible resilient action, or no resilient action, on the two arms 42.

The two arms 42 further include respectively two push buttons 44 which may be formed integrally therewith and which may protrude laterally out of the handle body 17, for instance through two holes 45 formed in said handle body (see FIGS. 1 a, 1 b and 2). The pushbuttons 44 may thus be surrounded by the handle body in all directions around the holes 45.

Returning to FIGS. 2, 8 a, 8 b and 10, the second ends 42 b of the arms 42 may include respectively two bearings, in particular two shell bearings 46 which are exposed toward the outside. Each shell bearing 46 may for instance include a cylindrical concave front face 46 a and a lateral edge 46 b which protrudes outwardly and which has also a cylindrical shape. The two front faces 46 a and the two lateral edges 46 b have the same cylindrical axis, corresponding to the axis of rotation of the shaving head 5.

As shown in FIG. 9, the rear face 5 c of the shaving head may include two inwardly facing arcuate slots 47 shaped in correspondence with the lateral edges 46 b of the shell bearings and adapted to receive said lateral edges for pivotally mounting the shaving head 5 onto the handle 2. These arcuate slots 47 may be formed respectively in two protruding ribs 48 and may be limited:

-   -   toward the handle, by a first arcuate concave surface 49 facing         toward the shaving head 5,     -   and away from the handle, by a larger second arcuate convex         surface 50 facing toward the handle 2.

The front faces 46 a of the shell bearings 46 bear respectively on the arcuate convex surfaces 50. Said arcuate convex surfaces 50 may include respectively two notches 51 for receiving corresponding protrusions 52 of the shell bearings 46 (see FIGS. 8 a and 8 b), so as to limit the angular range of rotation of the shaving head 5.

Besides, as shown in FIG. 9, the ribs 48 may include two inclined surfaces 53 facing each other and extending slantwise toward each other from the top of the ribs 48 toward the arcuate slots 47, so as to facilitate the insertion of the shell bearings 46 in the arcuate slots 47.

The rear face 5 c of the shaving head 5 may further include a central rib 54 having an edge forming a top cam surface 55 facing away from the shaving head 5 toward the handle 2. The cam surface 55 may have a generally V shape, and may for instance include two substantially flat surfaces 56 which are slightly inclined relative to one another and which may be for instance separated from one another by a notch 57 hollowed out in the rib 54 in order (e.g. to adapt the shaving head 5 on a other type of handle having a flexible tongue which is inserted into said notch 57).

Returning to FIGS. 2, 8 a, 8 b and 10, the lock/release mechanism 41 includes a plunger 58 which is movably mounted, substantially along the medial axis X between the two arms 42. This plunger 58 has a central body 59 and two lateral wings 60 extending opposite to one another toward the two arms 42. The central body 59 extends longitudinally parallel to the medial axis X, between a first, substantially flat free end 59 a which bears against the cam surface 55 of the shaving head, and a second end 59 b facing away from the shaving head 5. A recess 61 may be hollowed out in the central body 59, said recess forming a blind hole which opens at the second end 59 b of the central body 59, in the direction of the handle 2.

Each lateral wing 60 may include a detent 62 protruding parallel to the medial axis X toward the shaving head 5, said detent facing an inwardly extending protrusion 63 belonging to the corresponding arm 42. The protrusion 63 has an opening 64 which is limited inwardly by a rim 65 belonging to said protrusion. Besides, the lateral wings 60 of the plunger 58 may each have respectively two ribs 66 which extend in a medial plane of the arms 42, opposite to the central body 59.

The plunger 58 is elastically biased toward the cam surface 55 of the shaving head so as to cooperate therewith by camming action to bias said shaving head in rotation toward a rest position. In the example shown in the drawings, the plunger 58 is elastically biased by a spring 67, for instance a helicoidal spring, which has a first spring end fitted into the recess 61. The spring 67 also has a second spring end fitted into a recess 68, for instance in the form of a blind hole, hollowed out in an arm pusher 69.

The arm pusher is disposed between the arms 42 in line with the plunger 58 along the medial axis X. Said arm pusher 69 is disposed between the plunger 58 and the hinge 43 along the medial axis X. The recess 68 opens parallel to the medial axis X toward the plunger 58.

Besides, in the example shown in the drawings, the spring coils of the helicoidal spring 67 may be in mutual contact in a central portion of the spring 67, between the recesses 61, 68, and may be separate from each other between this central portion of the spring, except for the last spring coils at both ends of the spring.

The arm pusher is slidably mounted between the arms 42, substantially parallel to the medial axis X and is elastically biased by said spring 67 toward the handle, i.e. away from the shaving head 5. Said arm pusher 69 cooperates by camming action with the two arms 42 for biasing said arms outwardly away from each other, toward a head locking position shown in FIGS. 8 a, 8 b and 10, where lateral edges 46 b of the shell bearings 46 penetrate in the corresponding arcuate slots 47 of the shaving head.

The arm pusher 69 may have a central body 70 in which the recess 68 is hollowed out, and two lateral extensions 71 extending opposite to one another toward the two arms 42 and cooperating by camming action respectively with said two arms for biasing the arms toward the head locking position.

More particularly, the lateral extensions 71 may penetrate in two slots 72 formed respectively in the two arms and facing each other. The two lateral extensions 71 of the arm pusher may have lateral edges 74 which cooperate by camming action with the respective bottoms 73 of the slots. Said lateral edges may be diverging from the medial axis X in a direction away from the handle 2, whereas the bottoms 73 may also diverge from the medial axis in the direction away from the handle.

Thanks to these dispositions, the same spring 67 is used to bias the plunger 58 elastically toward the cam surface 55 of the shaving head and to bias the arm pusher 69 away from the shaving head, thus biasing both the shaving head in rotation toward the rest position and the arms 42 toward the head lock position.

It should be noted that, in the position of FIGS. 8 a, 8 b, and 10, the plunger 58 is maintained between the two arms 42 both by cooperation with the spring 67, by abutment against the cam surface 55 of the shaving head, and eventually by abutment against the protrusions 63 of the arms 42.

When a shaving head 5 is mounted on the handle 2, the lock/release mechanism 41 is normally in the head lock position. Starting from this position, when a user wishes to exchange shaving heads, he first pushes on both pushbuttons 44, which rotates the arm 42 toward each other against the camming action of the arm pusher 69. During this movement, the arm pusher 69 slides along the medial axis X toward the plunger 58, and said arm pusher partially penetrates between the ribs 66 of the plunger. When the arms 42 have sufficiently rotated toward each other to reach the head release position shown in FIG. 11, the head is released by the shell bearings 46 and is simultaneously ejected by the plunger 58.

The plunger 58 then moves forward to an outwardly protruding positions so that the detents 62 of said plunger penetrate in the recesses 64 of the extensions 63 of the arms. In this position, as shown in FIG. 11, the arms 42 are maintained in the head release position by abutment of the rims 65 against said detents 62, thus cooperating by hooking action. Afterwards, when a new shaving head 5 is fixed to the handle 2, the shell bearings 46 are inserted between the arcuate slots 47 of the new shaving head 5 and the cam surface 55 of said new shaving head pushes the plunger 58 backward toward the handle. The arms 42 are then released and rotate away from each other under the action of the arm pusher 69, so that the shell bearings 46 insert themselves in the arcuate slots 47 of the new shaving head, and the lock/release mechanism 41 is again in the position shown in FIGS. 8 a, 8 b and 10. 

1.-20. (canceled)
 21. A razor handle having a handle body and a lock/release mechanism including: two arms, each having a bearing for pivotally connecting a shaving head, the arms extending substantially symmetrically on both sides of a medial axis, the arms being elastically biased opposite to one another toward a head locking position wherein the bearings are adapted to pivotally bear the shaving head, and the arms being movable toward one another into a head release position wherein the bearings are adapted to release the shaving head; a plunger which is movable between the two arms, substantially parallel to the medial axis; and a spring biasing the plunger away from the handle body, such that the plunger is adapted to cooperate with a cam surface belonging to the shaving head for biasing the shaving head toward a rest position, wherein the lock/release mechanism further includes an arm pusher which is movable substantially parallel to the medial axis and which is biased toward the handle body by the spring, the arm pusher cooperating with the two arms by camming action for biasing the arms toward the head locking position.
 22. The razor handle according to claim 21, wherein the two arms are connected to one another by a hinge.
 23. The razor handle according to claim 21, wherein the arms are molded as a single piece, the hinge comprising a thin bridge of material connecting the two arms to each other.
 24. The razor handle according to claim 21, wherein each arm extends between a first end connected to the hinge and a second end including one of the bearings.
 25. The razor handle according to claim 24, wherein the bearings are shell bearings.
 26. The razor handle according to claim 25, wherein the arms are partially contained inside the handle body and the bearings are exposed toward the outside.
 27. The razor handle according to claim 21, wherein each arm includes a pushbutton which is adapted to protrude outside the handle body when the arms are in the locking position.
 28. The razor handle according to claim 21, wherein the two arms diverge from the medial axis in a direction away from the handle body.
 29. The razor handle according to claim 21, wherein the spring is a compression spring interposed between the plunger and the arm pusher in the medial direction.
 30. The razor handle according to claim 29, wherein the spring extends between two spring ends, penetrating respectively in a recess belonging to the plunger and in a recess belonging to the arm pusher.
 31. The razor handle according to claim 30, wherein the plunger has a central body and two lateral wings, the central body being adapted to cooperate with the cam surface of the shaving head to bias the shaving head toward the rest position, and the central body including the recess of the plunger which opens toward the arm pusher.
 32. The razor handle according to claim 30, wherein the plunger has a central body and two lateral wings, the two lateral wings of the plunger being adapted to cooperate by hooking action respectively with the two arms to maintain the arms in the head release position when the plunger is in an outwardly protruding position.
 33. The razor handle according to claim 32, wherein the lateral wings of the plunger are adapted to release the arms when the plunger is moved toward the handle body relative to the outwardly protruding position.
 34. The razor handle according to claim 33, wherein the lateral wings of the plunger include detents which protrude away from the handle body, substantially parallel to the medial axis, and the arms include two openings adapted to receive the detents to maintain the arms in the head release position when the plunger is in an outwardly protruding position.
 35. The razor handle according to claim 21, wherein the arm pusher has a central body and two lateral extensions cooperating by camming action respectively with the two arms for elastically biasing the arms toward the head locking position.
 36. The razor handle according to claim 35, wherein the two lateral extensions penetrate in two slots formed respectively in the two arms.
 37. The razor handle according to claim 36, wherein each slot has a bottom and each lateral extension cooperate by camming action with the bottom of the corresponding slot.
 38. The razor handle according to claim 37, wherein the two extensions of the arm pusher have lateral edges which diverge from the medial axis in a direction away from the handle body, the lateral edges bearing respectively on the bottoms of the slots, and the bottoms also diverging from the medial axis in the direction away from the handle body.
 39. The shaver including a razor handle according to claim 21 and a shaving head pivotally attached to the handle by the bearings, the shaving head including a cam surface and the plunger being elastically biased against the cam surface for biasing the shaving head toward a rest position.
 40. The shaver according to claim 39, wherein the bearings are shell bearings and the shaving head further includes two inwardly facing arcuate slots receiving respectively the two bearings.
 41. A razor handle having a handle body and a lock/release mechanism including: two arms, each having a bearing for pivotally connecting a shaving head, the arms extending substantially symmetrically on both sides of a medial axis, the arms being elastically biased opposite to one another toward a head locking position wherein the bearings are adapted to pivotally bear the shaving head, and the arms being movable toward one another into a head release position wherein the bearings are adapted to release the shaving head; a plunger which is movable between the two arms, substantially parallel to the medial axis; and a spring biasing the plunger away from the handle body, such that the plunger is adapted to cooperate with a cam surface belonging to the shaving head for biasing the shaving head toward a rest position, wherein the lock/release mechanism further includes an arm pusher which is movable substantially parallel to the medial axis and which is biased toward the handle body by the spring, the arm pusher cooperating with the two arms by camming action for biasing the arms toward the head locking position, and wherein the spring is a compression spring interposed between the plunger and the arm pusher in the medial direction.
 42. A razor handle having a handle body and a lock/release mechanism including: two arms, each having a bearing for pivotally connecting a shaving head, the arms extending substantially symmetrically on both sides of a medial axis, the arms being elastically biased opposite to one another toward a head locking position wherein the bearings are adapted to pivotally bear the shaving head, and the arms being movable toward one another into a head release position wherein the bearings are adapted to release the shaving head; a plunger which is movable between the two arms, substantially parallel to the medial axis; and a spring biasing the plunger away from the handle body, such that the plunger is adapted to cooperate with a cam surface belonging to the shaving head for biasing the shaving head toward a rest position, wherein the lock/release mechanism further includes an arm pusher which is movable substantially parallel to the medial axis and which is biased toward the handle body by the spring, the arm pusher cooperating with the two arms by camming action for biasing the arms toward the head locking position, and wherein the arm pusher has a central body and two lateral extensions cooperating by camming action respectively with the two arms for elastically biasing the arms toward the head locking position. 